Sheet feeding device



Jan. 7, 1958 H. J. 6055 SHEET FEEDING DEVICE Filed July 13, 1953INVENTOR. HAROLD J. GOSS ATTORNEYS United States sneer FEEDING DEVICEHarold J. Goss, Nashua, N. H., assignor to The International Paper HexMachine Company, Nashua, N. iii, a corporation of New HampshireApplication July 13, 1953, Serial No. 367,438

Claims. (Cl. 271-35) This invention relates to a sheet feeder andcarrier unit for individually and successively feeding each endmostsheet from a stack of flat sheets of uniform thickness and carrying thesheet away from the stack. It relates especially to top feeding magazineused in paper box folding machines for holding a stack of box blanksprior to their passage along the paper line of the machine to be formedinto a box.

It has heretofore been proposed to use as an envelope feeder in postagecancelling machines a power operated wheel or pulley having an elongatedprojection on its circumference and having a flexible belt around itsperiphery, the belt contacting the surface of the endmo-st envelope ofthe stack each time the projection passes thereunder. However, such beltfeeding mechanisms have usually been used together with a non revoluble,yieldingly mounted barrier, gate or separator element normally in thepath of advance of the endmost envelope or envelopes and required to beraised out of the path to permit the passage of a single endmostenvelope. Thus when the circumferential projection on the feed pulleylifts the belt into friction engagement with the endmost envelope, theenvelope is advanced under the yielding separator which risessufficiently to permit passage of one envelope but forms a barrier tothe next succeeding envelope. Usually such yielding separators have beenmounted on comparatively slow speed machines wherein the possibility oftoo much yielding is not a factor and the drag caused by thenonrevoluble separator is not important.

This invention, however, is intended for use on high speed machines foridentical flat sheets wherein it is essential that no double or triplefeeds occur, essential that unnecessary frictional drag on the sheets beeliminated and essential that wear on the friction elements be notsufiicient to cause frequent maladjustment of the moving parts.

It is the principal object of this invention to combine with such beltfeeding means, a separator means which is non yieldable and forms apassage of exactly the height of a single sheet thus positively assuringa feed of only one sheet at a time.

Another object of the invention is to provide a non yielding sheetseparator in which at least one of the passage forming elements isfreely revoluble in the direction of feeding, thus tending to preventany drag or retarding effect on a sheet moved through the passage.

Still another object of the invention is to provide means for retainingand guiding each sheet from where its lead ing edge exits from thepassage up to any desired location away from the stack, thus avoidingany gaps to be jumped or crossed by the sheets.

A further object of the invention is to provide a sheet feeder and sheetcarrier as a single unit, said unit including a single tension pulleyfor both the feeder and carrier and including a pair of smooth surfaced,nonyielding separator rolls which can be easily adjusted transverselyfor various widths of sheets.

A still further object of the invention is to provide belt feeder means,belt carrier means and nonyielding separator means in which a resilientspring at the passage of the separator means urges the leading edge ofeach sheet into the space between the belts of said feeder and carriermeans.

In the drawing,

Fig. 1 is a plan view of a preferred embodiment of the invention appliedto the top feeding magazine of a paper box folding machine with partsbroken away for clarity.

Fig. 2 is a side elevation of the device shown in Fig. l, and

Fig. 3 is a fragmentary plan view of the fixed non yielding gauges andthe resilient spring of the invention mounted on the lower front edge ofthe top feeding magazine.

As shown in the drawing M is the top feeding magazine of a paper boxfolding machine, such as is well known in the art. The magazine M has aninclined bottom 20, side walls or guides such as 21 and a lower front orforward edge 22, and is attached in any suitable manner to the frame Kof the paper box folding machine. A plurality of identical sheets suchas 0, each of uniform thickness, are fanned out in magazine M to form astack N and, in the case of a paper box folding machine, each sheet 0 isa box blank. The endmost sheet or blank 0 in stack N is designated bythe numeral 23 and inclines upwardly and rearwardly from its leadingedge 42 at or near the lower front edge 22 of magazine M.

The paper line of the box folding machine is indicated at P and sheetconveyor mechanism L is indicated for advancing each sheet such as Oindividually and successively along the paper line P. The sheet conveyormecha nism L is well known in the art and includes an endless chain 2'7trained around sprockets such as 28 and provided with a plurality ofspaced upstanding lugs 29 each lug arranged to engage the trailing edgeof a sheet 0 and advance the same along paper line P. A shaft 26 is provided for the sprockets such as 28 and there is usually a considerablegap between the lower forward edge 22 of magazine M and the lugs 29 ofconveyor mechanism L.

The sheet feeder and carrier unit of this invention includes nonyieldingsheet separator means A, a flexible friction feeder belt B and sheetfeeder means C.

The nonyielding sheet separator means A includesa nonyielding gauge suchas 30 and preferably a pair of such gauges 30 and 31, each of rigidmaterial such as bar metal and each positioned on an opposite side ofthe central longitudinal axis of magazine M along the lower forward edge22 of the bottom thereof. Each gauge such as is of L shape, one arm 32of the gauge having a hole 33 encircling a bolt 34 threaded in a fixedblock or bar 36. A coil spring 37 is positioned between the bar 36 andthe arm 32 whereby the gauge 30 is fixed in position but may be moved toother positions by rotating the head 38 of bolt 34. The other arm 39 ofgauge 30 extends upwardly and terminates in a tip 40, beveled at 41 andlocated in the path of the leading edge 42 of the endmost sheet 23 ofstack N.

Also included in sheet separator means A is a nonyi-elding roll such as43 and preferably a pair of such rolls t3 and 44, each of rigid materialsuch as metal and each nonyieldingly mounted to freely revolve around ashaft 45 which extends transversely above the pair of gauges 3i) and 31.Each roll such as .43 or 44 has a smooth, antifriction circumferentialsurface 47 or $8 and the surface of each roll is spaced the thickness ofa single sheet from the tip of one of the pair of gauges 3t and 31. Anonyielding passage 5%) is thus formed between the surfaces 47 and 48and the tips iii of gauges 3d and 31 the height of the passage beingadjustable to accommodate various thicknesses of sheets by means ofbolts such as 34. As indicated in Fig. 2, the leading edge 42 of eachendmost sheet 23 rests against the beveled portions 41 of gauges 30 and31 just in front of the passage 50, and while the rolls 43 and 44 are intangential contact with the exposed surface 51 of sheet 23, they have notendency to urge the same through passage 50 in view of theirantifriction surfaces 47 and 48. The freely revoluble smooth surfacedrolls 43 and 44 thus serve as the forward wall of the magazine M as wellas forming one side of the nonyielding sheet passage 50.

The sheet feeder means C of the invention comprises a feeder pulley, orwheel 60 mounted to rotate with the shaft 45 and having an elongatedcircumferentially extending projection, or bump 61 on its periphery. Theprojection 61 is provided With a gradually tapered leadmg edge portion62 and a gradually tapered trailing edge portion 63 which edge portionsmerge with the circumferential surface 64 of feeder pulley 60. Shaft 45is connected by suitable chains or belts not shown and well known in theart, to shaft 26 whereby it is power driven at high speed insynchronization with the sheet conveyor mechanism L.

A flexible friction feeder belt B is trained around the feeder pulley 60and extends rearwardly in the direction of feeding to a pulley 66carried by a transversely extending shaft 67. The upper stretch 68 offeeder belt B is inclined while the lower stretch 69 of belt B issubstantially horizontal to extend in prolongation of the paper line P,In the position shown in Figs. 1 and 2, the diameter of thecircumferential surface 64 of feed pulley 60 plus the thickness offeeder belt B is less than the diameter of the circumferential surfaces47 and 48 of the rolls 43 and 44, whereby the friction surface 70 ofbelt B does not touch the exposed surface 51 of endmost sheet 23 at itis moved past the same by pulley 60. I- Iowever, when thecircumferentially extending projectlon 61 of feeder pulley 60 is rotatedinto contact with the undersurface 71 of belt B by shaft 45, the belt Bis raised so that the diameter of the pulley 60, plus the thickness ofprojection 61 and the thickness of belt B is greater than the diameterof the rolls 43 and 44. Thus the friction surface 70 of belt B engagesthe exposed surface 51 of endmost sheet 23 and slides the leading edge42 thereof into and beyond the passage 50 formed by the nonyieldingseparator means A. The momentum achieved by the endmost sheet 23 frombelt B and feeder means C, together with the effect of further contactwith the lower stretch 69 of belt B tends to carry the sheet 23 up tothe position required for engagement in sheet conveyor mechanism L.

However, I prefer to provide an endless carrier belt D to firmly holdeach sheet against the lower stretch 69 of belt B as it travels acrossthe gap or space between passage 50 and conveyor mechanism L. Carrierbelt D is positioned below and opposite to belt B and is trained arounda pulley 80 carried by shaft 26 and around a pulley 81 carried by ashaft 82. Preferably, pulley 81 is located directly under feeder pulley60 with its shaft 82 extending below and parallel to shaft 45transversely of the machine. Pulley 81 is thus positioned just beyondthe passage 50 and close to the fixed gauges 3t} and 31. The lowerstretch 85 of belt D is inclined while the upper stretch 86 issubstantially horizontal in prolongation of paper line P and injuxtaposition with the lower stretch 69 of belt B. Each sheet 0 isreceived in the space between stretches 69 and 86 and firmly heldtherebetween until it is delivered to sheet conveyor mechanism L.

I also prefer to provide a resilient leaf spring E at the forward edge22 of magazine M and having one end 90 thereof fixed to a block 35 bybolts 91, 92, block 35 being slidably attached to bar 36 by bolt 97 inslot 98. The spring E is bent at right angles at 93 and its free end 94extends in the direction of feeding, in the plane of passage 50, to apoint beyond passage 50, proximate the 4 nip of belts B and D. As theexposed surface 51 of each endmost sheet 23 is engaged and slidablyadvanced by feeder belt B, the leading edge 42 thereof slides along thestraight upper surface 96 of leaf spring E and the leading edge portion42 of each sheet 23 is urged to follow a curved path conforming to thecurvature of the belt B rather than to travel in a straight line inextension of the flat plane of the endmost sheet in the stack. Thus theleading edge 42 is resiliently urged in a curved path into the spacebetween the stretches 69 and 86 of belts B and D and possibilities ofmalfunction are avoided. It should be noted that the upper surface 96 ofspring E extends in a straight line substantially tangential to thepulley 66), at passage 50, both in front and in rear of the passage thuspermitting each sheet to slide easily therealong.

Preferably also, a tension pulley or roll F is provided carried on theend of an arm 100, the opposite end of the arm being split at 101 andhaving a bolt 102 by which the arm may be tightened on shaft 67 undervarious clamping pressures as desired. Tension pulley F is so positionedthat it bears upon the lower stretch 69 of feeder belt B and at the sametime exerts tension on the upper stretch 86 of belt D.

In installing the feeder and carrier unit of this invention on boxfolding machines havingtop feeding magazines, the transverse shaft 26 ofthe existing conveyor mechanism is preferably utilized. The transverseshafts 45, 67 and 82 are added in the positions indicated in the drawingand pulleys 60, 81, 66 and 80 aligned preferably along the longitudinalcentre line of the machine on their respective shafts. Belts B and D arethen installed as are the nonyielding rolls 43 and 44. Gauges 30 and 31are mounted opposite rolls 43 and 44 and adjusted to the proper heightto form a passage 50 for the particular type of sheets or blanks to beused. In opera tion the freely revolving rolls 43 and 44 and gauges 30and 31 maintain the non-yielding passage 50 while projection 61 raisesbelt B with each revolution of feeder pulley to slide the endmostsheets, such as 23, individually and successively through passage 50'Tension pulley F maintains belts B and D at the proper tension whileeach sheet such as O is carried across the gap between passage 50 andconveyor mechanism L. Spring E continually urges the forward portion ofeach successive sheet into the nip of the belts B and D during theoperation of the unit.

At least one nonyielding sheet separator means A comprising a roll suchas 43 and a fixed gauge such as 30 and at least one flexible frictionfeeder belt B and sheet feeder means C are essential to the operation ofthe invention. Instead of positioning the belt B and roll 60 between twosheet separator means A as shown in the drawing, a single sheetseparator means A may be positioned between a pair of belts such as Band rolls such as 60, if desired.

I claim:

1. Apparatus for individually and successively sliding each endmostsheet from the end of a stack of sheets of uniform thickness, saidapparatus comprising nonyielding sheet separator means including afreely revoluble roll having a smooth antifriction circumferentialsurface in engagement with the exposed surface of each endmost sheet andforming one side of a nonyielding sheet passage equal in height to thethickness of a sheet and located along the leading edge of an endmostsheet in the stack; a flexible friction feeder belt having a stretchadvancing continuously from proximate the exposed surface of an endsheet in said stack along the plane of said passage and up to a sheetconveyor mechanism; sheet feeder means comprising a feeder pulley ofless radius than, and rotating co-axially with, said roll, said pulleynormally supporting said belt stretch out of contact with each endmostsheet but having an elongated circumferential projection with graduallytapered leading and trailing edges for periodically moving said feederbelt outwardly, radially beyond the periphery of said roll intofrictional engagement with the exposed surface of an end sheet of saidstack and sliding said sheet through said passage.

2. A combination as specified in claim 1 wherein said nonyielding sheetseparator means comprises said antifriction surfaced, freely, revoluble,roll and a fixed gauge opposite to, and spaced the thickness of a singlesheet from, the surface of said roll for forming the other side of saidnonyielding sheet passage and for forming a stop for the leading edge ofeach endmost sheet in said stack.

3. A combination as specified in claim 1 wherein said nonyielding sheetseparator means comprises a pair of laterally spaced apart gauges fixedbelow the path of the leading edge of said endmost sheet and a pair oflaterally spaced apart freely revoluble, smooth surfaced nonyieldingrolls, each having a portion of its smooth surface in contact with anendmost sheet and another portion of its smooth surface spaced thethickness of a single sheet above one of said fixed gauges, and saidfeeder pulley is mounted between said rolls and co-axially therewith.

4. A combination as specified in claim 1 wherein said sheet separatormeans includes rigid, stationary, stop means fixed in the path of thelower leading edge of the endmost sheet of the stack at the passage ofsaid sheet separator means.

5. A combination as specified in claim 1 plus a resilient leaf spring,fixed proximate the passage of said sheet separator means, said springhaving a straight, smooth surfaced free end extending substantiallytangential to the surface of said feeder pulley at a point beyond saidpassage in the direction of feeding and positioned to urge the leadingedge of each endmost sheet into a curved path conforming to the curve ofthe circumference of said feeder pulley.

6. A combination as specified in claim 1 plus an endless carrier belthaving a straight stretch continuously advancing in juxtaposition withand at the same speed as said stretch of said feeder belt, and having apartly circular stretch advancing in the direction of feeding justbeyond said passage and in the path of an endmost sheet emerging fromsaid passage.

7. A combination as specified in claim 6 plus a tension pulley, mountedbetween said passage and said conveyor mechanism, in contact with theundersurface of the stretch of said feeder belt that is in juxtapositionwith said straight stretch of said carrier belt for simultaneouslykeeping both said stretches under tension.

8. A feeder and carrier unit for individually and successively slidingeach endmost sheet from the end of a stack of sheets of uniformthickness, said unit comprising the combination of nonyielding sheetseparator means including a smooth surfaced, freely revoluble rollengaging said stack and cooperable with a fixed gauge for forming anonyielding sheet passage, equal in height to the thickness of one saidsheet, adjacent the leading edge of said endmost sheet; an endlessfriction feeder belt continuously advancing adjacent said passage andspaced from the exposed surface of said endmost sheet; a feeder pulleyco-axial with said roll and supporting said belt, said pulley having acircumferential projection adapted to periodically move the adjacentportion of said belt outwardly, radially beyond the periphery of saidroll into a position of engagement with the exposed surface of eachendmost sheet until said belt has moved the leading portion thereofthrough said passage; and a carrier belt, cooperable with said feederbelt for receiving each sheet advanced through said passage and firmlyholding the same against the feeder belt while travelling away from saidstack.

9. A combination as specified in claim 8 plus resilient spring means andoperable beyond said passage proximate said sheet separator means forurging the leading edge portion of each endmost sheet, advanced throughsaid passage, into the space between said feeder belt and said carrierbelt.

10. A feeder and carrier unit for individually and successively slidingeach topmost sheet from a stack of identical sheets in the top feedmagazine of a paper box machine, said unit comprising a pair ofnonyielding gauges spaced apart on opposite sides of the lower frontedge of said magazine; a pair of smooth surfaced rolls, nonyieldinglymounted on a shaft extending transversely above said gauges to freelyrevolve in the direction of feeding with the smooth surfaces thereof incontact with each topmost sheet, said rolls being spaced apart on saidshaft and each positioned opposite one of said gauges to form anonyielding passage therehetween, equal in height to the thickness of asingle sheet; a feeder pulley positioned between said pair of rolls andmounted to co-axially revolve with said shaft independently of saidrolls in the direction of feeding, said pulley having an elongatedcircumferentially extending projection thereon; an endless feeder belttrained around said feeder pulley and extending in the direction offeeding, said feeder belt being adapted to engage and slide each endmostsheet into said passage with each revolution of the projection on saidfeeder pulley; an endless carrier belt extending in the direction offeeding below, and opposite to, said feeder belt and arranged to firmlyhold each sheet advanced through said passage against said feeder beltas said sheet is carried away from said passage and a resilient leafspring, positioned between said pair of nonyielding gauges and havingits free end extending beyond said passage, said free end being normallyout of contact with an endmost sheet but moved radially out- Ward beyondthe periphery of said rolls to urge the leading edge portion of eachendmost sheet into the space between said feeder belt and said carrierbelt.

References Cited in the file of this patent UNITED STATES PATENTS1,380,483 La Bombard June 7, 1921 1,399,288 Bowes Dec. 6, 1921 1,626,386Bronander Apr. 26, 1927 1,955,066 Hiller Apr. 17, 1934 1,956,229Sidebotham Apr. 24, 1934 2,080,968 Krell May 18, 1937 2,339,835Burkhardt Ian. 25, 1944

